Anti-blocking packer

The invention discloses an anti-blocking packer, which comprises a center pipe, a sand prevention center pipe, an upper joint and a lower joint, wherein the upper part of a seam between the sand prevention center pipe and the center pipe is provided with a sealing ring; a sliding center pipe is arranged outside the center pipe in a sleeving way; a rubber tube is wrapped outside the sliding center pipe; an upper sealing head and a lower sealing head are arranged at the two ends of the sliding center pipe; the sliding center pipe, the rubber tube, the upper sealing head and the lower sealing head form a movable whole; the movable whole can freely slide on the center pipe; the middle part of the center pipe is provided with a first pressure transfer hole; a second pressure transfer hole is formed in the outer wall of the sliding center pipe; and a pressure transfer passage is formed between the center pipe and the sliding center pipe. During the fracturing, the peristaltic force of a pipe column is counteracted by the motion between the sliding center pipe and the center pipe; the rubber tube and a sleeve cannot move; the rubber tube cannot be damaged; the sealing is reliable; the seam between the center pipe and the sand prevention center pipe achieves a good sand prevention effect, so that sand cannot enter the rubber tube; and the rubber tube can easily contract. The anti-blocking packer has the advantages that the deblocking is easy; the structure is simple; and the cost is low.